Organosiloxane compositions that cure to yield crosslinked silicone rubber sealants by the reaction of polyorganosiloxanes containing at least two reactive groups per molecule with organosilicon compounds containing at least three reactive groups per molecule as the crosslinker are known. The reactive ingredients of these compositions are typically packaged in two containers with the crosslinker in one container and a reaction catalyst in a second container. The curing reaction occurs when the contents of the two containers are mixed.
Many approaches to flame resistance depend on the addition of several ingredients, including oxide fillers and platinum. For example, Wolfer et al. in U.S. Pat. No. 5,008,317 describe flame retardant and arc resistant silicone elastomers which contain an additive obtained by mixing a vinyl-rich polydiorganosiloxane, a metal oxide selected from titanium dioxide, zirconium dioxide, zinc oxide, Ce(III) oxide, Ce(IV) oxide, platinum, and an organosilicon compound having a basic nitrogen bonded to the silicon. DeLaTorre et al. in U.S. Pat. No. 4,102,852, describe a self-extinguishing room temperature vulcanizable silicone rubber composition comprising a silanol end-stopped polydiorganosiloxane polymer, a metal oxide filler, an alkoxy functional cross-linking agent, carbon black, platinum, and a titanium chelate catalyst.